‘Sx1 PHENOMENA OF ORGANIC NATURE 385 
- course, he expected he would get no infusorial 
- animalcules at all in that infusion; but, to his 
great dismay and discomfiture, he found he almost 
- always did get them. 
Furthermore, it has been found that experi- 
~ ments made in the manner described above answer 
well with most infusions; but that if you fill the 
vessel with boiled milk, and then stop the neck 
_ with cotton-wool, you will have infusoria. So that 
_ you see there were two experiments that brought 
pe to one kind of conclusion, and three to an- 
_ other; which was a most unsatisfactory state of 
_ things to arrive at in a scientific inquiry. 
_ Some few years after this, the question began 
to be very hotly discussed in France. There was 
_M. Pouchet, a professor at Rouen, a very learned 
man, but certainly not a very rigid experimental- 
ist. He published a number of experiments of his 
_ own, some of which were very ingenious, to show 
that if you went to work in a proper way, there 
"was a truth in the doctrine of spontaneous genera- 
tion. Well, it was one of the most fortunate things 
'M. Pasteur, to take up the question on the other 
side ; and he has certainly worked it out in the 
most perfect manner. Iam glad to say, too, that 
he has published his researches in time to enable 
me to give you an account of them. He verified 
all the experiments which I have just mentioned 
m VOL. II ee 
